Electric discharge can develop when atmospheric air is exposed to high voltage potentials between two electrodes. When this occurs, an avalanche effect is created, which is caused by the voltage (consisting of electrically loaded molecules) colliding with neutral molecules and changing them to be electrically loaded. This heavily electrically loaded zone creates ozone and nitrogen oxides from the atmosphere. When an isolator, either insulating or conductive, is placed between the two electrodes, the avalanche effect is avoided and the result is a cloud of ionized air. This ionized air or corona discharge can be used for surface treatment of a number of insulating and conductive materials which show poor or no adhesion properties to other materials, such as printing inks, adhesives, and other insulating and conductive materials. The configuration of the electrode which is to be used for surface treatment can be a line source, such as a wire or roller, or an area source, such as a shoe, a plate or a rectangular-shaped ceramic, or a point source, such as a needle. A point source offers advantages over the line and area source, but its design is critical to achieve the optimum corona discharge without effecting the frequency of the generator.